@prof.566
Tu vas rigoler mais moi je pense que je suis tomber sur ce qui a servi de cahier des charges pour le casque US du f-35. Tous les éléments de langage de LM par rapport à leur casque est là.
THE TOPSIGH HELMET
FIRST MODEL
Photo Sextant
Photo Sextant
one article about the Topsight helmet :
©SIGNAL Magazine 1996
French Helmet Visors Clear The Skies for Combat Pilots
Seeing is believing for aircraft and helicopter operators receiving a host of new sensor and control data visually.
By Robert K. Ackerman
Aviators flying new fighter aircraft and helicopters can receive increased amounts of combat-critical information through helmet displays employing new image collection and projection technologies. These advanced visor display systems can provide pop-up data on aircraft capabilities, threat status and vehicle systems, with some devices also projecting day or night imagery from internal helmet-mounted cameras.
This visor display technology serves as a two-way sensory input/reception device designed to direct the pilot's attention to suddenly emerging threats. The head motion generated by a pilot turning to face a new threat is translated into target acquisition for lock-on commands to the aircraft's weapons systems. The same visor that provides alert directions just a few centimeters in front of a pilot's eye displays targeting and firing activities as the pilot acts to engage and destroy the adversary.
These visual cues soon will be augmented by audio directions working in tandem to reduce the pilot's reaction time. Voice commands will take the place of hands-on-stick measures to provide a rapid response to air combat demands.
These new helmet display systems are being developed by Sextant Avionique, Velizy-Villacoublay, France. Much of this emerging technology builds on company research that explored pilot efficiency under a wide range of manual, audio and visual cues and inputs (SIGNAL, October 1993, page 17). Many of these capabilities are being incorporated incrementally into helmet systems for the Rafale advanced fighter aircraft and the Tiger attack helicopter.
Pilots flying air combat missions in France's most advanced fighter aircraft soon will be tracking and targeting enemy aircraft with little more than a nod of the head. The Topsight helmet-mounted display, designed for air-to-air combat in the Rafale, provides aircraft status and targeting symbology on the pilot's visor.
In combat, the aircraft's sensor suite detects a potential target and supplies that information to the helmet system, which presents these data on the visor and directs the pilot where to turn his head to face the target. The pilot then uses the helmet's head-tracking system to designate the adversary for elimination. Using controls on the hands-on throttle and stick, the pilot can lock a missile onto a target, designated by pointing the helmet, without needing to turn the aircraft toward it.
Paul Beck, product manager for export helmets at Sextant Avionique, cites flight trials demonstrating that--in the target acquisition role--a pilot can acquire a target visually at twice the distance attainable using a normal display system. The aircraft's radar or a missile sensor effectively tells the pilot where to look by placing symbology on the helmet visor. The display is projected onto the visor using a 0.5-inch, high-resolution cathode ray tube system for high-contrast viewing during full daylight conditions.
Beck explains that this display system is monocular and provides an imagery eye relief of 60 millimeters (2.4 inches). This distance between the pilot's eye and the internal surface of the first optical element improves the pilot's ability to use the superimposed imagery.
In addition to target locations, the display includes Rafale heading, attitude, altitude, missile and radar acquisition angles, firing domain, weapons stores, missile firing envelopes, airspeed and aircraft energy. Visual cues before and after missile lock alert the pilot to each target designation, lock-on and attack firing status.
The helmet employs an alternating current magnetic tracking system common to several Sextant helmets. An electromagnetic transmitter in the cockpit is teamed with an electromagnetic receiver in the helmet to create an alternating current magnetic field within the cockpit. This field is detected in the helmet, and software algorithms help to determine the line of sight and the pilot's head position. Symbology in the visor display moves with the pilot's head to illustrate where the helmet is pointed.
The entire headgear is fully integrated, especially with regard to the visor and oxygen mask. Beck explains that this is necessary to permit the pilot to endure a 625-knot ejection, which rules out employing modular components. The total weight of the helmet system is 1.45 kilograms (3.2 pounds).
The Topsight helmet-mounted display currently is undergoing flight qualification trials using a Mirage 2000 testbed aircraft. These flights, which began last year, cover symbology, target acquisition and designation, pilot comfort and system stress. The system has been tested at 9 gravities without any loss of display capabilities. Beck notes that the system can be adapted to suit any of a number of advanced fighter aircraft.
Building on the air-to-air combat helmet display system is the company's Topnight helmet, which is configured for nighttime air-to-ground Rafale missions. Where the Topsight helmet provides a single-eye view of display data, the Topnight helmet differs from its air-to-air cousin by the inclusion of an image-intensified charge-coupled device (CCD) camera and binocular display of scenery.
The Topnight display features all the characteristics, including symbology and information, employed in Topsight. Added to this is either a forward-looking infrared (FLIR) image from an aircraft sensor or a night vision image-intensified scene from the small in-helmet CCD. In addition to targeting missiles, the helmet's electromagnetic head tracker also can aim the aircraft's FLIR. The pilot's own head motion directly aims the CCD.
Both eyes view the same display of cursive-drawn symbology atop video imagery. The pilot can switch between the external FLIR image or the light-intensified image from the helmet-mounted camera. The imagery display capabilities also allow the pilot to view video received through a direct link from an outside source.
The binocular display also provides a 60-millimeter eye relief. The pilot's field of view is 40 degrees x 30 degrees. The helmet's raster video display can provide infrared, image-intensified or television imagery. The fully integrated Topnight helmet, with its oxygen mask, weighs 1.8 kilograms (4 pounds).
While Topnight is optimized for air-to-ground and night roles, its commonality with Topsight enables pilots to wear it during daytime air-to-air missions. Topnight is due for flight trials later this year, as soon as the Mirage 2000 is configured for the helmet's capabilities. In addition to display technology, the company is developing an audio cue system and a voice recognition system for the Rafale.
The integrated helmet approach flies in the face of requirements for helicopter pilots, however. Different configurations for helicopters mandate different display systems, and the absence of high-speed ejection allows designers to incorporate modular capabilities in helmets.
Future enhancements to helmet-mounted visor technology likely will focus on providing non-visual cues and feedback to complement existing display technologies, Beck predicts. One such effort employs active noise reduction to decrease unwanted sounds and to provide for clearer radio reception and audio cues. The company also is integrating a vocal command system for the Rafale that currently is being flight tested on the Mirage 2000. It can recognize 150 words, with a maximum of 10 words per command.
Also in development is a three-dimensional spatial sound system for the Rafale helmet. This system would aid pilots by providing direction-specific cues. A pilot would hear a tone alert that seemingly originates from the direction of the threat. This would inform the pilot where to turn his head to acquire the threat visually. Sensor information from the aircraft would generate a tone indicating both direction and type of threat, such as air-to-air or ground-to-air, for example.
Beck explains that recent tests have focused on evaluating the time taken to detect a threat visually under different conditions. These range from a baseline of an ordinary helmet without any symbology or sound, to symbology only and to a combination of symbology and spatial sound. Results seem to indicate that each added sensory input decreases the time a pilot needs to detect a threat.
This mixed sensory input system probably will see flight trials in 1997, Beck warrants. The three-dimensional spatial sound will be the first of these upgrades to be integrated into the Rafale, he adds. The display system for the Rafale helmet is complete, with evaluations focusing on further developments of the system's symbology.
Similar improvements loom on the horizon for the helicopter helmets as well. With the Topowl helmet being flight tested on the Tiger, the company will begin testing the day/night helmet on the South African Rooivalk attack helicopter. All of the Rafale and helicopter helmets could be applied to other countries' aircraft as well, Beck adds.
Photo Sextant
http://flight.gear.free.fr/VVCUS.html
